This has been studied on warmth retaining properties with various air velocity, density and thickness at the condition of horizontal wind as the constant wind lather. The transmission rate of air decreased with increasing the Backingh density of the first 5mm of air inlet part of the sample and with increasing heavy thirkness. In the thermal equilibrium state, the translmssion area which is le. is influence of air velocity was detected in sample thickness 20mm and packing density 0.0,3891cm 3. The changes of warmth retaining ratio was closely related to the rhanre of Iran Hision of air velocity, and then it is increased as thickness increase at low air.